1. Field of the Invention
The present invention relates to a bonding device for manufacturing a liquid crystal display device, and more particularly, to a bonding device for manufacturing a liquid crystal display device with an ionizing device.
2. Discussion of the Related Art
In general, recent developments in the information communication field have increased demand for various types of displays devices. In response to this demand, various flat panel type displays such as liquid crystal display (LCD), plasma display panel (PDP), electro-luminescent display (ELD), and vacuum fluorescent display (VFD) have been developed. These are used as displays for various equipments.
In particular, LCD devices have been used because of their high resolution, lightweight, thin profile, and low power consumption. In addition, LCD devices have been implemented in mobile devices such as monitors for notebook computers. Furthermore, LCD devices have been developed for monitors of computer and television to receive and display image signals.
Efforts to improve the image quality of LCD devices contrast with the benefits of high resolution, lightweight, thin profile, and low power consumption. In order to incorporate LCD devices as a general image display, image quality such as fineness, brightness and large display area, for example, must be realized.
The process of manufacturing an LCD device in a related art includes forming a sealant pattern on one of the first and second substrates to form an injection inlet, bonding the first and second substrates to each other within a vacuum processing chamber, and injecting liquid crystal material through the injection inlet. In another process of manufacturing an LCD device according to the related art, a liquid crystal dropping method, which is disclosed in Japanese Patent Application No. 11-089612 and 11-172903, includes dropping liquid crystal material on a first substrate, arranging a second substrate over the first substrate, and moving the first and second substrates to be adjacent to each other, and bonding the first and second substrates to each other.
Compared to the liquid crystal injection method, the liquid crystal dropping method is advantageous in that various processes such as, formation of a liquid crystal material injection inlet, injection of the liquid crystal material, and sealing of the injection inlet are unnecessary since the liquid crystal material is predisposed on the first substrate. To this end, a variety of apparatuses for applying the liquid crystal dropping method have been recently researched.
FIGS. 1 and 2 show cross sectional views of a substrate assembly device using the liquid crystal dropping method according to the related art. In FIG. 1, the substrate assembly device includes a frame 10, an upper stage 21, a lower stage 22, a sealant dispenser (not shown), a liquid crystal material dispenser 30, a processing chamber including an upper chamber unit 31 and a lower chamber unit 32, a chamber moving system 40, and a stage moving system 50. The chamber moving system 40 includes a driving motor driven to selectively move the lower chamber unit 32 to a location where the bonding process is carried out, or to a location where the outflow of the sealant and dropping of the liquid crystal material occur. The stage moving system 50 includes another driving motor driven to selectively move the upper stage 21 along a vertical direction perpendicular to the upper and lower stages 21 and 22.
A process of manufacturing a liquid crystal display device using the substrate assembly device of FIGS. 1 and 2 is explained. First, a second substrate 52 is loaded on the upper stage 21, and a first substrate 51 is loaded upon the lower stage 22. Then, the lower chamber unit 32 having the lower stage 22 is moved to a processing location by the chamber moving system 40 for sealant dispensing and liquid crystal material dispensing. Subsequently, the lower chamber unit 32 is moved to a processing location for substrate bonding by the chamber moving system 40. Thereafter, the upper and lower chamber units 31 and 32 are assembled together by the chamber moving system 40 to form a vacuum tight seal, and pressure in the chamber is reduced by a vacuum generating system.
Then, the upper stage 21 is moved downwardly by the stage moving system 50 at the above-mentioned vacuum state so as to closely contact the second substrate 52 fixed to the upper stage 21 to the first substrate 51 fixed to the lower stage 22. Further, the process of bonding the respective substrates to each other is carried out through a continuous pressurization, thereby completing the manufacture of the LCD device. Thus, after the bonding of the substrates is completed, the upper and lower chamber units 31 and 32 are separated from each other, and the lower chamber unit 32 is moved to an unloading position by the chamber moving system 40, and the bonded substrates are unloaded.
However, the substrate assembly device according to the related art is problematic. First, when upper and lower stages are pressed to bond the two substrates to each other, glass substrates may break due to excessive pressure and equipment error. An operator will remove the broken glass pieces but such broken glass pieces may not be easily and completely eliminated thus reducing an adhesive strength of a sealant and degrading liquid crystal property. Second, while the process of loading and unloading the substrates is repeated, particles on the substrates remain inside the chamber, which degrades bonding. Third, static electricity may occur to damage inner circuits of the liquid crystal display device.